EMC2302 Standard Microsystems Corp., EMC2302 Datasheet - Page 41

• Manufacturer Part Number: EMC2302
• Description: Rpm-based Pwm Fan Controller
• Manufacturer: Standard Microsystems Corp.

Dual RPM-Based PWM Fan Controller
Datasheet
SMSC EMC2302
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Zoom on
Output
Output
PWM
Update Time ends, PWM duty cycle changed
Output
PWM
Output
PWM
10x
PWM
10x
Spin Up Routine Ends – begins normal
27000
26800
26600
26400
26200
26000
25800
25600
25400
25200
25000
-50
Spin Time = 1.0s; Spin Level = 55%; Updated Time = 200ms;
t = 0
RPM Target from 0 RPM -> 8000 RPM @ time t = 0
RPM Target from 0 RPM -> 8000 RPM @ time t = 0
PWM Frequency vs. Ambient Temperature
Update Time = 200ms; Max Step = 16 PWM counts
V
DD
FSC Algorithm Spin Up Routine
operation
= 3.3V, Base Frequncy = 26Khz
FSC Algorithm PWM Ramping
0
Ambient Temperature (°C)
Duty Cycle Measured = 53.8%
Duty Cycle
T emp er at ur e ( C )
Measured
50
100
Update Time ends, PWM duty
cycle changed
150
DATASHEET
41
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Output
PWM
Output
PWM
10x
27000
26800
26600
26400
26200
26000
25800
25600
25400
25200
25000
2.95
Spin Time = 1.0s; Spin Level = 50%; UpdateTime = 200ms;
t = 0
RPM Target from 0 RPM -> 8000 RPM @ time t = 0
FSC Algorithm Spin Up Routine – NoKick
3.05
PWM Frequency vs. Supply Voltage
TA = 25C, Base Frequncy = 26Khz
3.15
Duty Cycle Measured = 50%
Supply Voltage (V)
3.25
3.35
Revision 1.2 (03-22-10)
3.45
3.55
3.65